1. Field of the Invention
Example embodiments of the present invention relate generally to flat panel display fabrication. More specifically, example embodiments of the present invention relate to printing apparatuses for manufacturing a spacer, and methods of manufacturing a display panel.
2. Description of the Related Art
Generally, a liquid crystal display (“LCD”) device includes an LCD panel displaying images by controlling the transmittance of a liquid crystal layer, and a light providing assembly providing light to the LCD panel. The LCD panel includes a first substrate on which a thin-film transistor (“TFT”) is formed to act as a switching element, and a second substrate facing the first substrate. The liquid crystal layer is interposed between the first and second substrates.
The LCD panel typically also includes a plurality of spacers disposed between the first and second substrates. Each spacer is a member for maintaining a cell gap, or a distance between the first and second substrates. When the LCD panel is depressed by an external force, the spacers act to restore the cell gap to its original state. The spacers may be manufactured on the first substrate or the second substrate, and may be fabricated via a photolithograph process by using a photoresist. Alternatively, the spacers may be manufactured by distributing the spacers onto the first substrate, or a light-blocking area of the second substrate, through a mask. As a further alternative, the spacers may be manufactured by printing the spacers on the light-blocking area of the second substrate.
The printing method has been widely used to manufacture spacers due to its superior resolution, capability for use in manufacturing large size devices, and good printability. The printing method is generally performed by providing a printing roller with beads coated onto a printing plate, and transferring the beads onto a substrate. These beads become the spacers. However, concave portions of the printing plate often do not pick up any beads, which often results in a non-uniform coating of spacers on the substrate, where some areas contain an insufficient number of spacers. This results in areas of the substrate in which the cell gap cannot be maintained, or is easily collapsed, resulting in display defects such as spots or flickers, which reduce display quality.